The largest money laundering scandal yet uncovered has been back in the spotlight. 200 billion Euros were allegedly laundered through a tiny Estonian branch of the Danish Danske Bank between 2007 and 2015. The whistleblower who first alerted Denmark's biggest bank to the problem testified in front of the Danish parliament this week. Once upon a time, money laundering meant setting up pizzerias as fronts and building blocks of flats to rent. But things have become more sophisticated. Today's perpetrators are smurfing - investing small amounts in many small businesses, moving dirty money around with crypto currencies and setting up companies within companies within companies. Ruth Alexander and a panel of expert guests discuss how money laundering is done and the ways the authorities can take control of the problem.

(Photo: Rolled up US dollars. Credit: Getty Images)